This work focused on physicochemical property assaying, fatty acid composition, triacylglycerol (TAG) profiles, and unsaponifiable matters composition of the Chinese evening primrose oil. The cold press oil possessed very low acid value and peroxide value, and relatively high iodine value. Fatty acid composition results indicated that this oil was especially high in linoleic acid and linolenic acid. Characterization of TAG composition was achieved by a two-dimensional HPLC coupling of nonaqueous reverse-phase and silver ion HPLC with atmospheric pressure chemical ionization MS method. There was a total of 38 TAGs including 27 regioisomers which had been determined. Unsaponifiable matters composition results revealed that this oil possessed a number of phytosterols, in which β-sitosterol and stigmasterol were most predominant.
Keywords: evening primrose oil; physicochemical property; triacylglycerol; unsaponifiable matter.